Textile Dyeing Wastewater Treatment

DAF Dissolved Air Flotation for Textile Dyeing Wastewater Treatment
Textile dyeing wastewater is complex in its constitution, the main pollutions in wastewater are: Fibers, Oiling Agent, Dyes, etc.

Textile dyeing wastewater has the below characteristics:
1. Large water quantity/flow rate.
2. Deep/dark color
3. Alkaline in pH
4. Big water quality and quantity changes

Due to the different dyes and chemical additives used in textile processing, the pH value, COD_Cr, and BOD₅, etc. vary greatly in different textile processing wastewater. The typical textile dyeing wastewater quality is:
COD: 1500-1750 mg/l
BOD: 500-600 mg/l
TSS: 200-300 mg/l

Generally, pH of textile dyeing wastewater is 7.8-9.5, or even higher.
Use an Automatic pH Regulator to dose Acid into wastewater to adjust water pH. Then feed textile dyeing wastewater to dissolved air flotation by pump.

And dose flocculant and coagulant into and thoroughly mix with wastewater for flocculation reaction to coagulate the colloidal particles and micro suspended solids to conglomerate the particles into bigger clusters.

Dissolved air flotation will release millions of tiny bubbles into water, these bubbles attach to, and form within, the solids or chemical flocculants entering the vessel, causing them to float to water surface where they are retained and forms scum layer, which is then subsequently removed by DAF skimmer.

Dissolved air flotation removes the most part of color and suspended solids(TSS), also will remove part of BOD and COD, greatly reduce the pollution loads for the subsequent biological treatment process.